灰阶编码掩模制作微光学元件

Coding Gray-Tone Mask for Fabrication of Microoptical Elements

提出一种基于改变灰阶编码掩模的单元形状和位置的掩模设计新方法 ,并根据成像过程中的非线性因素 ,用这种方法对掩模图形进行了预畸变校正。根据部分相干光成像理论和抗蚀剂曝光显影模型 ,模拟计算了这种灰阶编码掩模产生的空间光强分布和光刻胶上的浮雕结构。采用电子束曝光系统制作了这种掩模 。

A new method was proposed to design coding gray-tone masks, based on modifying position and shape of cell on mask. Predistortion applied to modify mask was implemented by introducing this method according to the nonlinear effects in aerial image and resist development. Based on the theory of partial coherent light imaging and the resist development model, the intensity distribution through the coding gray-tone mask and the exposure of photoresist were simulated. The coding gray-tone mask was fabricated by electron beam exposure system, and the microlens array with continuous relief distribution on photoresist was obtained.